This invention relates to methods for bonding valve face and cylinder bearing interface areas in bores of a steel barrel for multiple piston pumps and it more particularly relates to methods of metallurically bonding bearing material in bores of the steel barrel.
In the use of hydraulic pumps and motors of the rotary cylinder barrel type, such as is disclosed in the Galliger U.S. Pat. No. 3,169,488, high speed and high pressure are both generally required, and thus it is necessary to provide bronze friction surfaces in the bores of a steel cylindrical barrel having multiple bores. A problem in bonding bronze friction surfaces in these bores has been to prevent fluid leakage that can take place if the metallurgical bond between the bronze and the steel is faulty because of gas remaining in the bonding area, for example, during solidification of the bronze bearing material in the bonding process. Therefore in the bonding method of the prior art patents, the construction of the pumps and motors is costly in that there is a high percentage of rejection because of fluid leakage through the bonding joints at high pressure operation.
An object of the present invention is to provide an improved method for bonding bearing material within bores in steel barrels of fluid pumps and motors which substantially obviates one or more of the limitations and disadvantages of the described prior art systems.
Another object of the present invention is to provide a less costly method of constructing hydraulic pumps and motors.
Other objects, purposes and characteristic features of the present invention will be in part obvious from the accompanying drawings, and in part pointed out as the description of the invention progresses.